On July 6, 2017, at the EPS Conference on High Energy Physics in Venice, the LHCb has reported the observation of Ξcc++(Xicc++) which is a new particle containing two charm quarks and one up quark. Although the existence of this baryon had been predicted by the Quark Model, physicists have been looking for this baryon for many years. Its mass has been reported to be about 3621 MeV (here is the link for the LHCb report).

It is important to have in mind that in the paper Calculation of almost all energy levels of baryons I had predicted for this baryon a mass of 3710 MeV which means an error of only 2.4%. Please, take a look at this paper with its erratum (click here for the erratum).

It is also important to mention that on January 5, 2013, the CDF Collaboration reported the “Evidence for the bottom baryon resonance state Λb*0 with the CDF II detector”, arXiv:hep-ex 1301.0949. According to CDF its mass is about 5.92 GeV. This level of Λb0 had been predicted in the above paper Calculation of almost all energy levels of baryons with a mass of 5.93 GeV, just 0.17% off.

In the old version of the above paper (from 2002), Calculation of the energy levels and sizes of baryons with a noncentral harmonic potential, (https://arxiv.org/abs/hep-ph/0209064) I predicted that Ξc would have levels with masses 2.82 GeV, 3.01 GeV and 3.13 GeV (on page 8 of the paper) and since then the following levels have been found 2.79 GeV and 2.815 GeV; 2.93 GeV, 2.98 GeV and 3.055 GeV; 3.08 GeV and 3.123 GeV. Of course, the new version of the paper took these levels into account.

Therefore, the above paper Calculation of almost all energy levels of baryons can help experimentalists from LHCb to find new levels of baryons.

Summary of the predicted baryon levels with their measured and predicted masses.

Baryon Level

Measured Mass(Gev/c2)

Predicted Mass(GeV/c2)

Error in %

Ξcc++

3.621

3.71

2.45

Λbo*

5.92

5.93

0.17

Ξc(2a)

2.79

2.82

1.07

Ξc(2b)

2.815

2.82

0.18

Ξc(3a)

2.93

3.01

2.73

Ξc(3b)

2.98

3.01

1.00

Ξc(3c)

3.055

3.01

1.47

Ξc(4a)

3.08

3.13

1.60

Ξc(4b)

3.123

3.13

0.22

In the above table I labeled the Ξc levels according to Table 7 from the above mentioned paper Calculation of almost all energy levels of baryons.

A paper, related to this above paper, is the paper The Radii of Baryons which calculates the radii of allmost all baryon levels. One of the predicted radii was already confirmed. For viewing the paper, please click here.

While refereing a paper today, September 03, 2017, I realized that I forgot to include in the above list the discovery of the Xib- and Xib0 baryons reported by LHCb on January, 3, 2015 with masses 5.7949 GeV/c^2 and 5.7931 GeV/c^2. In the above paper Calculation of almost all energy levels of baryons I had predicted for them the mass 5.81 GeV/c^2, just 0.9% off.

The correctness of the paper Calculation of almost all energy levels of baryons is quite in line with other works in this web page on quark compositeness and mean that constituent quarks are the true quarks and are massive particles, and thus, valence quarks (which are almost massless) are not quarks, and are, actually, prequarks called primons by me.

It is also worth taking into account that the MIT-Bag Model, which has some success, would be completely meaningless if quarks were point-like, that is, if a baryon were a system of three point-like particles. The MIT-Bag Model takes into account the overall effect of the interactions of the six prequarks arranged in three quarks and forming two layers of prequarks. That is why in the Bag Model one considers boundary conditions at a surface and outward pressure. Please, take a look at the post The article PLOT OF THE WEEK – QUARK COMPOSITENESS IS NOWHERE NEAR is wrong in this web page.